1. Related Applications
The present application claims the priority benefit of Korean Patent Application No. 10-2014-0007163, filed on Jan. 21, 2014, incorporated by reference herein.
2. Field of the Invention
The present invention relates to functionalized carbon nanoparticles prepared by modifying the surface of the carbon nanoparticles with C5-10 aryl or heteroaryl substituted with one or more hydroxyl groups, and functional polymer fibers bound therewith.
3. Description of the Related Art
All carbon nanomaterials have attracted a keen interest since carbon nanotubes and graphenes emerged as potential functional nanomaterials. The presence of π-orbitals and long conjugated structures in these carbon nanomaterials make possible various functionality, such as electrical conductance, chemical reaction sites, black color, etc. In particular, most carbon nanomaterials exhibit outstanding physicochemical and mechanical stabilities compared to other organic materials. Given this, carbon nanomaterials have been utilized as electronic materials in various applications.
Of all these carbon nanomaterials, carbon nanoparticles (CNPs), so-called graphites or carbon blacks, have also been widely used for electrode materials, anti-static materials, additives for tires and paints, etc., through physical mixing techniques. However, minimal attention has been paid to the binding of carbon nanoparticles to polymer fibers. The carbon nanoparticles are basically hydrophobic and thus they aggregate or agglomerate in water, whereas the widely used polymer fibers, such as polyesters, polyamides, polyketones, etc., have polar groups. For this reason, the binding of carbon nanoparticles to polymer fibers is restricted.
However, the binding of carbon nanoparticles to polymer fibers provides the functionality of carbon nanoparticles in addition to that of polymer fibers, and thus is useful for the development of functional fibers. Accordingly, technology for improving the binding of carbon nanoparticles to polymer fibers is required.
Conventionally, the use of dispersing agents such as a sodium salt of polynaphthalene sulfonic acid has been suggested (C. Wang, X. Zhang, F. Lv and L. Peng, J. Appl. Poly. Sci., 2012, 124, 5194). However, this method cannot resolve the intrinsic issue of the carbon nanoparticles in relation to their degree of dispersion and stability in water. Theoretically, a strong base (e.g., NaOH) may be employed to form hydroxyl groups on the surface of carbon nanoparticles as reported in several literatures (N. Tsubokawa, A. Funaki, Y. Hada and Y. Sone, J. Polym. Sci., Polym. Lett. Ed., 1982, 20, 27; D. D. H.-P. Boehm, D. E. Diehl, D. C. W. Heck and D. C. R. Sappok, Angew. Chem., Int. Ed. Engl., 1964, 3, 669). Unfortunately, this method also has a drawback in the separation of unreacted strong base that can cause significant damage to the polymer surface. In addition, the interaction between the formed hydroxyl groups in the carbon nanoparticles and the polar groups in the polymer chain is actually unstable because hydroxyl groups are much smaller in size relative to the carbon nanoparticles.
Accordingly, the present inventors have made extensive efforts to develop a method for introducing carbon nanoparticles to polymer fibers. As a result, they found that functionalized carbon nanoparticles whose surfaces are modified with C5-10 aryl or heteroaryl substituted with one or more hydroxyl groups can excellently bind to polymer fibers, thereby completing the present invention.